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		| microccd 
 
 
 Joined: 08 Aug 2006
 Posts: 10
 
 
 
			    
 
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				| wrong state of pic16f876 |  
				|  Posted: Tue Sep 26, 2006 3:40 pm |   |  
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				| I program and test the pic16f876, most of time, it works fine. but sometime when I turn on the power switch, it was in wrong state(wrong output). I shut it down then turn it on again, it will have the correct output. what may cause that? thanks a lot! |  | 
	
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		| PCM programmer 
 
 
 Joined: 06 Sep 2003
 Posts: 21708
 
 
 
			    
 
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				|  Posted: Tue Sep 26, 2006 3:54 pm |   |  
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				|  	  | Quote: |  	  | But sometime when I turn on the power switch, it was in wrong state(wrong output) | 
 Make sure you have the correct #fuses settings.   Make sure you
 have the ones shown in bold below:
 
 #include <16F877.H>
 #fuses XT, NOWDT, NOPROTECT, BROWNOUT, PUT, NOLVP
 #use delay(clock=4000000)
 #use rs232(baud=9600, xmit=PIN_C6, rcv=PIN_C7, ERRORS)
 //====================================
 void main()
 {
 
 while(1);
 }
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		| microccd 
 
 
 Joined: 08 Aug 2006
 Posts: 10
 
 
 
			    
 
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				|  Posted: Tue Sep 26, 2006 4:03 pm |   |  
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				| the following is what i'm using, are they correct? 
 
 
  	  | Code: |  	  | 
 #include <16f876.h>
 #device ICD=TRUE
 #fuses HS,NOWDT,NOLVP,PUT
 #use delay(clock=20000000)
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		| PCM programmer 
 
 
 Joined: 06 Sep 2003
 Posts: 21708
 
 
 
			    
 
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				|  Posted: Tue Sep 26, 2006 4:13 pm |   |  
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				| Did you read my post ?    Look at the item shown in bold below. Put it in your code !
 
 #include <16F877.H>
 #fuses XT, NOWDT, NOPROTECT, BROWNOUT, PUT, NOLVP
 #use delay(clock=4000000)
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		| microccd 
 
 
 Joined: 08 Aug 2006
 Posts: 10
 
 
 
			    
 
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				|  Posted: Tue Sep 26, 2006 4:23 pm |   |  
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				| yes, but what's the function of BROWNOUT? thank you. |  | 
	
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		| PCM programmer 
 
 
 Joined: 06 Sep 2003
 Posts: 21708
 
 
 
			    
 
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